Check for NotFound fault during DeleteVolume

[chethanv28]

What this PR does / why we need it:
For delete operation invoked explicitly for PVCs which have no FCD in the backend, VC does not trigger a task and it returns "Fault". This PR will introduce a check for the type of FAULT ==> specifically NOTFOUND and write this info in the log and return nil to safely complete the delete operation.

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

Special notes for your reviewer:
Added logs below to indicate how not found scenarios will behave with the change

Release note:

Check for NotFound fault in DeleteVolume

Logs:

{"log":"I0905 21:23:10.700394       1 manager.go:311] DeleteVolume: volumeID: \"26e74e3f-98ac-45a9-ad20-812222d7e098\", opId: \"0fdd675e\"\n","stream":"stderr","time":"2019-09-05T21:23:10.701551387Z"}
{"log":"I0905 21:23:10.700499       1 manager.go:331] DeleteVolume: Volume deleted successfully. volumeID: \"26e74e3f-98ac-45a9-ad20-812222d7e098\", opId: \"0fdd675e\"\n","stream":"stderr","time":"2019-09-05T21:23:10.70155599Z"}
{"log":"I0905 21:23:10.700513       1 vsphereutil.go:161] Successfully deleted disk for volumeid: 26e74e3f-98ac-45a9-ad20-812222d7e098\n","stream":"stderr","time":"2019-09-05T21:23:10.701559396Z"}
{"log":"DeleteVolume called: %s 26e74e3f-98ac-45a9-ad20-812222d7e098\n","stream":"stdout","time":"2019-09-05T21:23:24.321170845Z"}
{"log":"I0905 21:23:24.313152       1 controller.go:306] ControllerGetCapabilities: called with args {XXX_NoUnkeyedLiteral:{} XXX_unrecognized:[] XXX_sizecache:0}\n","stream":"stderr","time":"2019-09-05T21:23:24.321253147Z"}
{"log":"I0905 21:23:24.319077       1 controller.go:149] DeleteVolume: called with args: {VolumeId:26e74e3f-98ac-45a9-ad20-812222d7e098 Secrets:map[] XXX_NoUnkeyedLiteral:{} XXX_unrecognized:[] XXX_sizecache:0}\n","stream":"stderr","time":"2019-09-05T21:23:24.32126154Z"}
{"log":"I0905 21:23:24.319128       1 vsphereutil.go:155] vSphere Cloud Provider deleting volume: 26e74e3f-98ac-45a9-ad20-812222d7e098\n","stream":"stderr","time":"2019-09-05T21:23:24.321264872Z"}
{"log":"I0905 21:23:24.410204       1 vsphereutil.go:161] Successfully deleted disk for volumeid: 26e74e3f-98ac-45a9-ad20-812222d7e098\n","stream":"stderr","time":"2019-09-05T21:23:24.414882662Z"}
****************************************************************************************************************************************************************************************************************************************************************
{"log":"E0906 06:46:24.706823       1 manager.go:292] VolumeID: \"c8e231a2-95ab-490e-8053-cc56609aba51\", not found. Returning success for this operation since the volume is not present\n","stream":"stderr","time":"2019-09-06T06:46:24.707203568Z"}
****************************************************************************************************************************************************************************************************************************************************************

[k8s-ci-robot]

Hi @chethanv28. Thanks for your PR.

I'm waiting for a kubernetes-sigs or kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[codenrhoden]

/ok-to-test

[codenrhoden]

/test pull-vsphere-csi-driver-build
^ nothing to do with this PR, I just want it to re-run so I can look at a log file. :)
I asked @divyenpatel about this, and he's asked to hold off on merging until after 1.0.1 is tagged.
/hold

[codenrhoden]

/test pull-vsphere-csi-driver-build
one more try... I'm checking that the build is using the latest csi-ci image, which I recently updated. This will ensure that everything is built with Go 1.12.10. We were using an older version previously.

[chethanv28]

@codenrhoden and @divyenpatel Please review and see if the "do-not-merge/on-hold" tag can be removed on this PR

[chethanv28]

/assign @divyenpatel
/assign @codenrhoden
/assign @dvonthenen

[divyenpatel]

/lgtm

[divyenpatel]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chethanv28, divyenpatel

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• OWNERS [divyenpatel]

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[divyenpatel]

/hold cancel